Author: vsapsai Date: Tue Jun 26 10:56:48 2018 New Revision: 335638 URL: http://llvm.org/viewvc/llvm-project?rev=335638&view=rev Log: [Sema] Fix infinite typo correction loop.
NumTypos guard value ~0U doesn't prevent from creating new delayed typos. When you create new delayed typos during typo correction, value ~0U wraps around to 0. When NumTypos is 0 we can miss some typos and treat an expression as it can be typo-corrected. But if the expression is still invalid after correction, we can get stuck in infinite loop trying to correct it. Fix by not using value ~0U so that NumTypos correctly reflects the number of typos. rdar://problem/38642201 Reviewers: arphaman, majnemer, rsmith Reviewed By: rsmith Subscribers: rsmith, nicholas, cfe-commits Differential Revision: https://reviews.llvm.org/D47341 Modified: cfe/trunk/lib/Sema/SemaExprCXX.cpp cfe/trunk/test/Sema/typo-correction.c Modified: cfe/trunk/lib/Sema/SemaExprCXX.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExprCXX.cpp?rev=335638&r1=335637&r2=335638&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaExprCXX.cpp (original) +++ cfe/trunk/lib/Sema/SemaExprCXX.cpp Tue Jun 26 10:56:48 2018 @@ -7727,12 +7727,8 @@ Sema::CorrectDelayedTyposInExpr(Expr *E, if (E && !ExprEvalContexts.empty() && ExprEvalContexts.back().NumTypos && (E->isTypeDependent() || E->isValueDependent() || E->isInstantiationDependent())) { - auto TyposInContext = ExprEvalContexts.back().NumTypos; - assert(TyposInContext < ~0U && "Recursive call of CorrectDelayedTyposInExpr"); - ExprEvalContexts.back().NumTypos = ~0U; auto TyposResolved = DelayedTypos.size(); auto Result = TransformTypos(*this, InitDecl, Filter).Transform(E); - ExprEvalContexts.back().NumTypos = TyposInContext; TyposResolved -= DelayedTypos.size(); if (Result.isInvalid() || Result.get() != E) { ExprEvalContexts.back().NumTypos -= TyposResolved; Modified: cfe/trunk/test/Sema/typo-correction.c URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/typo-correction.c?rev=335638&r1=335637&r2=335638&view=diff ============================================================================== --- cfe/trunk/test/Sema/typo-correction.c (original) +++ cfe/trunk/test/Sema/typo-correction.c Tue Jun 26 10:56:48 2018 @@ -87,3 +87,16 @@ __attribute__((overloadable)) void func_ void overloadable_callexpr(int arg) { func_overloadable(ar); //expected-error{{use of undeclared identifier}} } + +// rdar://problem/38642201 +struct rdar38642201 { + int fieldName; +}; + +void rdar38642201_callee(int x, int y); +void rdar38642201_caller() { + struct rdar38642201 structVar; + rdar38642201_callee( + structVar1.fieldName1.member1, //expected-error{{use of undeclared identifier 'structVar1'}} + structVar2.fieldName2.member2); //expected-error{{use of undeclared identifier 'structVar2'}} +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits